**Want to know your IQ and don’t have much time to answer a dozen of questions? Try the world’s shortest IQ test called the Cognitive Reflection Test (CRT). It has only 3 questions.**

CRT was developed in 2005 by Shane Frederick from Princeton and was published in the Journal of Economic Perspectives.

- The test attempts to find out how you think: do you trust your gut feelings or do you take time to think rationally?
- CRT identifies how good you are in intuitive thinking and analytical thinking.
- However, getting all three answers correct is not the only parameter of having a higher IQ. Your speed of answering determines this too.

**Before proceeding to the test, just be careful. Don’t rush into answering the questions. Think clearly and use common sense.**

**Here are the 3 questions:**

1. The total price of a bat and a ball is $1.10. The price of the ball is $1 more than the bat. So, what is the price of the bat?

2. 5 machines take 5 minutes to make 5 widgets. In order to have 100 widgets, how long will 100 machines take?

3. There is a patch of lily pads in a lake. The patch doubles in size every day. If the lake gets covered in 48 days, then how many days should it take to cover half of the lake?

**The correct answers are:**

1. 5 cents.

2. 5 minutes.

3. 47 days.

**How to solve them?**

1. Let the cost of the ball be

Then, cost of the bat is x+$1.

Therefore, total cost= Bat+ Ball = x+ (x+1)= 1.10.

Calculating,

x=0.05.

So, the cost of the ball is 5 cents.

2. 5 machines make 5 widgets in 5 minutes.

Therefore, 1 machine will make 1 widget in 5 minutes.

Thus, 100 machines will make 100 widgets in 5 minutes.

3. The lily pad doubles in size every day. So, it will cover half of the pond in 47 days.

**Usually, the most popular answers are:**

1. 10 cents.

2. 100 minutes.

3. 24 days.

*How many of these did you get correct?*